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Topic: Robot needs to lift more than its own weight (Read 7642 times)

I have a robot made out of vex parts. I need to be able to lift an approximately 7-pound plexiglass box (no top or bottom). I'd like to use suction cups to do this. But with its current build, the robot doesn't have enough force to even get full suction against the box, let alone lift it back onto itself. What would be the best way to accomplish this, gearing it down or something else?

It can be any shape I like but it has to fit within 30cmx30cmx30cm (the box). Basically the goal of the event I'm doing is to end up with a bunch of objects inside this box. The objects are easy enough to move into a 30cm space but I need to lift and lower the box over them, though at the end the robot can still be suctioned to the box if I don't have a way to remove it. Also, the box has 5 balloons inside that ideally would end up with 3 popped but still inside the box. 2 of the balloons have to end up outside of the box.

I'm guessing you start out with the box not attached to the robot? rather than building a suction cup strong enough to lift such a heavy box i suggest that you build an arm with a little shelves at the end and sides to scoop up the box and then you can raise and lower the arm to trap objects. I also suggest you make the arm as short as possible to make it more stable, also put most of your weight on the back. ( assuming your arm is in front)

The robot does not start attached to the box, no. And time is a factor, so it would likely take less time to push all the objects together and move the box on top of them than to move everything into the box. Here is the arena: http://www.soinc.org/events/robotram/RRplayfield08.pdf

I already have it all built with the suction cups. My main problem is that I can't exert enough force to get full suction on the box. The second problem is that it seems like the Vex servos just ARE NOT strong enough, even geared down, to lift the box.

I'm not using an arm or forklift. I just have a panel mounted to tilt back and forth (its mounted in the middle). Either way, I likely need higher torque motors... What about getting the suction itself to work?

Though that still would be helpful, I suppose. Here is a picture, I apologize for the horrible quality, it was taken on a phone... That panel on the right has 4 suction cups on it and its mounted on the two motors at the front on the right.

Yes. Its too weak to push the suction cups on. If I manually suction it on and tilt the platform back (without holding the box at all), the box doesn't fall off. The suction caps are pretty strong and the box is only like 6lbs.

this is the main reason i didn't get a vex kit. i got two 1/4 scale servos up front with near 200 oz-in torque to do the same job as you did, and i think it's working pretty well. the nationals box with steel corner reinforcements is 5lbs 8oz. if your robot isn't strong enough to drive into the robot, figure out what other sort of attachments you can make to the box (strong double sided tape maybe?). well anyway i just got my parts today im in school right im gonna work all after school til like 10pm. lol the shits saturday we're so screwed.

is there a guide that can explain how to build a forklift? or like how it works? im not really sure... because that would be EXTREMELY helpful.and hey how did yours go mine did horrible cuz mine wouldn't stick to the box either. water didnt help. i wonder hwo the guy on youtube did it so effortlessly.

The competition is already over. I eventually got it to work using a sort of clamp on the top of my panel. But the robot ended up too heavy and its gears got caught in the playing field rug so it didn't move very far.